I've read a few threads on this topic before and have came to the conclusion that bekit's kernals are the culprit. After testing this on Koush's last 3 CyanogenMod versions, I can pretty well say that switching to p3droid's kernals may help you. With my experience it is NOT setCPU or rom manager causing this issue. I was only able to get about 6 hours out of my battery with bekit and with p3droid I can go all day and still have 30% left by the time I go to bed. I was testing this with both of their 1 Ghz kernals, it may differ with kernal speeds. Also TURN OFF live wallpapers, its kills your battery. Hope this helps someone!